Disclaimer:

I have no longer v2014.5 installed.

1) Take a look in

MIDI/Audio menu > Quantization Settings > More Settings…

There are two options for allowing dotted rests.

Are they selected or de-selected?

Yes, I know. It sounds crazy that a settings for rests would affect notes. Just One Of Those Things.

2) Also, take a look in

Preferences - Edit > the pane Automatic Settings

Is the option Automatic Music Spacing selected or de-selected?

Thank you so much Peter!

Those particular suggestions didn't work, but they led me to a solution that did: In that MIDI/Audio menu there is the Retranscribe option. With a few test measures selected this feature re-wrote the rhythms using dotted notes thus eliminating the unnecessary ties. Only problem is that it also removed any mark tied to the note (i.e. articulations, slurs/phrase marks). Marks tied to beats (hairpin dynamic, all expressions, etc.) were left intact. I saved the score as a different name and reopened the original. With it I selected all and retranscribed. I then went back to my "safety" file and copied just articulations and smart shapes attached to notes to the retranscribed original and it seems to have worked.

Thanks again for the pointer in the right direction!

I use Retranscribe a lot because I’ve never found the quantization settings very robust or helpful. Thank heaven as well for the JW Rhythm Copy plug-in as well as the Patterson Beam Selection plug-in. 

And, thank you David, that explains why my 16ths were converted to 8ths. Not very many in this particular score so it will be easy to copy back from my safety copy. Note to self: quantitize to shortest note value prior to retranscribing .. Thanks again both of you!